I cannot think of very many areas where we atheists, humanists, skeptics, and/or freethinkers can bring about meaningful change all by ourselves. Even if we look at the few things most (though certainly not all) of us have in common, we are quite limited in what we can do with regard to any one of them. We probably can't bring about significant improvements in reality-based education, preserve separation of church and state, end discrimination against atheists, or stop our elected officials from pursuing religiously-motivated policies detrimental to the public good all by ourselves. To produce the sort of change many of us are interested in, we have to be able to work with each other. We are probably even going to need to build coalitions that include religious believers.
Perhaps we could do it on our own if more secular individuals were interested in activism and willing to organize. If we could figure out how to effectively mobilize non-theists around issues like the separation of church and state, our numbers could not be ignored. But this doesn't seem to be happening. For many issues, even those as basic as the separation of church and state or free speech, it often seems like we have an easier time finding allies in the form of religious minorities (e.g., non-Christian religious believers). And that means that those of us who are interested in such issues need to be ready, willing, and able to work with religious believers on shared goals.
I know some atheists are not interested in any sort of activism, and that is their choice to make. I know it seems like some atheists are addicted to outrage and are more interested in calling people names on the Internet than in bringing about any sort of social change. But I also know that there are many of us who are interested in improving our world for ourselves and others. For us, it seems inevitable that learning how to work effectively with others, including theists, is going to be important.
I think one of the greatest challenges we face when it comes to working with theists is how to strike the balance between being true to ourselves and maintaining productive working relationships. Working with religious believers does not mean that we must feign respect for religious belief, but it does mean that we need to respect the individual believers with whom we are working. It also means that we need to be willing to set aside some of our feelings toward religion from time-to-time in order to focus on what we are trying to accomplish. For example, if I am working with LGBT Christians to promote marriage equality, I am going to be focused on the work we are doing instead of criticizing Christianity. This does not mean that I cannot criticize Christianity in other contexts, only that I probably won't do so in this one.
If you think about all the various minority religions in the U.S., it will be obvious that the adherents of some of them face similar bigotry from the Christian majority as do atheists. If we expect them to help us work to reduce bigotry against atheists, we need to be ready to help them reduce bigotry against their them. For some atheists, working to reduce bigotry against pagans, Wiccans, Satanists, Muslims, and other religious minorities may be tough to swallow. They may get hung up on the notion that religion is the problem rather than bigotry. They may be unable or unwilling to view these religious minorities as allies. For other atheists, this may be a non-issue as long as the shared goals are important enough.
Of course, nothing I just said is limited to religious belief. There are plenty of ludicrous beliefs out there that can pose obstacles. Each of us has somewhat different thresholds for the sort of inaccurate or irrational beliefs we can live with in order to advance our goals. Some of us might be able to work with Christians but not with persons who subscribe to various New Age belief systems (e.g., crystals, auras) without mocking these beliefs. Others would have little difficulty working with persons with such beliefs as long as the goal they are working on is sufficiently important to them. The key is for each of us to figure out what our various limits and thresholds are and use that knowledge accordingly. I need to know, for example, whether I can work with someone who is convinced that genetically modified foods are dangerous and that legally mandated labeling is essential (I can).
Coalition building is probably going to be necessary for us to accomplish much of what we want to accomplish. It is rarely an easy task but seems to be one we will need to learn how to navigate effectively if we are serious about bringing about the sort of change many of us say we want.